The invention herein described may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.
The present invention relates to anti-ship missile proximity fuzing and more particularly to anti-ship missile proximity fuzing wherein improvements have been provided to prevent prefunctioning on either the surface of the sea or extraneous targets. There are no suitable proximity fuzes available or previously proposed for anti-ship application. Those fuzes which have been proposed or used for this purpose suffer from the defect of prefunctioning on the surface of the sea or the target and preclude the more effective contact detonation. This has led to the practice of using contact type fuzes only for anti-ship weapon application. The use of this type fuzing results in the omission of potential kills on high near-miss trajectories of the weapon.
The present invention provides a fuzing system which will give optimum warhead burst control on near-miss trajectories and will not prefunction on either the surface of the sea or target for those trajectories that would ultimately collide with the target. The system can utilize either a pulsed microwave or optical system to provide the received signals and timing inputs to a logic circuit. The logic circuitry effectively produces a sea tracking gate in the antenna beam which illuminates the sea surface. Also produced in the antenna beam is a target gate which is shorter in range than the sea gate and is slaved to the sea gate. This allows the target gate to expand and contract with the sea tracking gate as the missile flies over the sea but is prevented from actually detecting the sea surface. The presence of a ship target in the antenna beam results in an abrupt signal appearing in the target gate which causes the target gate to hold at a fixed value independent of the sea tracking gate, and causes the firing circuit to arm.
Accordingly, an object off the invention is to provide an improved anti-ship missile fuze having automatic ranging.